[vladorlov96]

hey guys, I'm new to the BMW family but I have an issue which I hope I can get answers for. I have a 2011 e90 335i JB4 tuned. Also I have aftermarket downpipes and a chargepipe. Now, every day or so I keep getting a check engine light that tells me about catalytics and o2 sensors. which I just clear with JB4 app and it goes away. The errors are
38A4:No description found
38B4:No description found
3106 Catless downpipes installed.

I also ran the codes with FiXD which is another scanner tool and it gives me catalytic converter and o2 sensor errors. Now, I assume, CEL comes on because of downpipes. car runs and drives great, not feeling any difference. Did anybody have the same issue before? please help!!

[HiRev335i]

Your more than likely getting the codes because of your downpipes. Jb4 alone no longer has auto clear to keep those codes at bay when running catless. Your other alternative is to run MHD which does. Or you can add the BEF along with your Jb4 and if anyone else could also chime in..... if I am correct that'll work as well.

[Dambaehaseyo_e92]

Originally Posted by HiRev335i

Your more than likely getting the codes because of your downpipes. Jb4 alone no longer has auto clear to keep those codes at bay when running catless. Your other alternative is to run MHD which does. Or you can add the BEF along with your Jb4 and if anyone else could also chime in..... if I am correct that'll work as well.

What do you mean JB4 no longer has auto clear? I still have mine on and it auto clears the CEL. I occasionally turn it off just to make sure nothing else is wrong with the car. The first two codes he has are tuner codes and the downpipe which is perfectly normal.

[orteeze]

Newest firmware doesn't allow auto clear is what he's talking about.

[Tonkatoy]

Originally Posted by orteeze

Newest firmware doesn't allow auto clear is what he's talking about.

Originally Posted by orteeze

Newest firmware doesn't allow auto clear is what he's talking about.

yea they took it off. you just have to go to 1 and 2 on jb4 on the steering while.

is it a catless downpipe. if so go to area 74 and buy the chip

[orteeze]

Put a back end flash using MHD and disable the code in tuner pro. Use your Google Fu powers; it can be done fairly easy. You won't regret it.

[vladorlov96]

Originally Posted by orteeze

Put a back end flash using MHD and disable the code in tuner pro. Use your Google Fu powers; it can be done fairly easy. You won't regret it.

Thanks! another question, does back end flash do anything else good besides clearing off errors? sorry never had to deal with it before ((

[orteeze]

Originally Posted by vladorlov96

Thanks! another question, does back end flash do anything else good besides clearing off errors? sorry never had to deal with it before ((

Here's a link to N54tech where you can find the information you need.

https://www.n54tech.com/forums/showthread.php?t=43151

[Bullcitybmmer]

If you were to search MY POST HISTORY you might find the answer to this.

Go to n54tech, download the appropriate BEF bin. Download tunerpro, and code it out- Boom, no more CEL. I'm not sure that the BEF adds any more power, but it does add driveability. It effectively has the JB4 only controlling boost, and the BEF controlling your timing, fueling, etc.... it's just all around much smoother, and I'd say it's worth doing.

[vladorlov96]

Thanks for all your replies!! will be doing further research and hopefully get the BEF process going